Self-determining perimeter



Sept. 30 1924.

H. MCI. MORTON SELF DETERMINING PERIMETER Filed March 5 1921 2 Sheets-Sheet l IJMMAW/ Sept. 30, i924..

- H. MCI. MORTON SELF DETERMINING PERIMETER Filed March 5. 1921 2 Sheets-Sheet 2 I/V VE /V T 0)?. MS I. MM raw. Y lf/.s fr0/MEX W f MMM 5p Patented Sept. 30, i924.

asian lTFlGfE;

SELF-DETERldlNITG ERMETER.

Application led March 5, 1921.

To all whom t may concern Be it lmown that l, HOWARD lilo-l. MoR'roN, a citizenV of the United States, residing at Minneapolis. in the county ol' Hennepin and State oit ldinnesota, have invented certain new and useit'ul improvements in Seli-Determining Perimeters; and l do hereby de- Clare the ollowii to be a full, clear, and exact description ci the invention, such as will enable others skilled in the art to which it appertains to malte and use the same.

This invention relates to an optica-l instrunient and particularly to such an instrument called a perimeter which is use-d to examine and determine the range oit vision of the eye. rlhe instrument also embodies a portion which is constructed to be used as a scotometer.

lt is an object ot this invention to provide a perimeter which the patient can himseit quickly and accurately manipulate to determine the range ot vision.

lt is a further object of the invention. to provide a perimeter having a plurality oi tiXed spaced meridians so that the range or vision can be universally determined without the necessity of adjusting or swinging the meridians about a center or pivot point. lt is another object of the invention to equip such a perimeter with a central disk constituting a scotometer which will in no way interiere with the operation ot the perimeter proper.

Still another object ot the invention is to produce such an instrument which vis nicely balanced on the supportingf means, and the parts ot which are especially constructed so as not to interfere with the eilicient 'tunctioning et the instrument.

These and other objects and advantages oi4 the invention will become apparent 'from the vollowing description mede in connect-ion with Athe accompanying drawings in which like vreference characters refer to the same parts throughout the diilcrent views., and in which,

Fig. l represents a view in 'front elevation of the instrument;

Fig. 2 is a central vertical section of the same;

Fig. 3 is a partial view in elevation of the rear portion of the instrument;

Fig. 4 is a fragmentary View on an enlarged scale oi one ot the meridians and sight objects;

Serial No. 449,944'.

Fig. 5 is a tranverse section on the line 55 oi Fig'. 4t;

Fig. 6 is a central vertical section through the gun sight and support therefor;

Fig. is a view showing one et the meridians showing the graduations thereon g and Fig. 8 is a fragmentary view showingI a modified lform oli' the invention.

Referring to the drawings, the device comprises a supporting member l having at one end a depending handle if ezt any suitable and convenient forni The member l, at its other end, has an upstanding post l and a bracket member lh is connected to the post and has termed therein a rectangu lar groove le. An annular rim member is secured in the groove lc by a spaced head and countersunk screws 3. The member 2 is shown as ot flat rectangular cross section but it will be understood that this member may have any convenient or desired shape. A plurality ot' equally spaced meridian members 4l have their ends terminating and fixedly secured in the member 2. The meridians l curve in substantially circular form rearwardly from the member 2 and converge toward the center of an annular ring 5 and have their edges disposed in the body of said ring and rigi idly clamped thereto by a retaining ring Ve held in place by suitably spaced headed screws extending therethrough and into the ring 6. It will be seen that the mer lian members 4E lie in substantially the surface ot a sphere, the center ot which is disposed a short distance inside of the rim member 2 at the center thereofn in open work cage structure is thus termed and light can readily pass between all of said members fl. rlhe meridian or rib members l substantially rectangular in cross section but have small. preferably', rectangular grooves i'ornied therein at each side thereof, as shown in Fig. 5. rfi plurality ot sight object members Z are constructed of flat material to embrace the members l and have projections extending inwardly into the slots in the sides thereof'. rlhe members 7 have a portion la disposed on the inner side of the members a, which is shown as oit substantially circular form and these members are provided on the outside of the members t with suitable ilat handles or linger-pieces 7b. rlhe members I are adapted to slide on the members 4 and Il O red and the one nearest the centri will have its inner surface colorel rhe einen. screws retaining` the alato 6 ir noe" made suiicieiitly long te 8 which is thus secured to of the memloe s 4.

rThis plat i shown iii l, is Git parativeljy small diameter, but there is suf icient extent etV the same between the ring;

6 and the edee thereor" 1 D bers or the three men 7 to be disposed therebehind.

plate 8 is markedor graduated rit rr hnes constituting` diameters thereoi arranged at equal angular distances een.

A plurality of circles SQ' are also en the disk and suitable grafiliation.-` placed on certain ot' the diameters t t intersection with the circles. These line which are inscribed on this lr a1 l marked thereon, the disk itself ben on its innerv surface. The disk also oval spaced marks 8b thereon di i, What below its horizontal diainetr. disk, so marked, constitutes a the use ot' which Will be Well inde. these skilled in the art. Extendingly and upwardly from each sid bracket lb are r ds l, the vertical. part et which is disposed substantielljiT in alignment with the center et the sphere and these rodsare again bent to extend ii horizontall),i at their upper ends and converge and are formed with a head ineinber le. The member ln is formed vwith a flat front surface and gunsigit member 9 is pivotallj.7 secured thereto by hei l screw X ending into the said bead. member 9 is provided with a small sim aperture 9u, the axis et which coincides Witl the horizontal axis of the sphere outlined by the members il. rThe niemeer .i small Hat spring l0 secured thereto at i e upper end by a ii/et or other suiti-tilening means7 and this spring eilte` VYW ilus

il". lower part of the said member and i 10a supported therein and -xtendii an aperture in the member 9. When the member 9 is in `ipstaiiein position, as shown in l.. rec' a small aperture fornieerin the hold the member 9 in this gosit' engagement of the pin l0 WitlA t1 1s so slight that the member 9 can b d head ie turned on its pivot to depend downrtar if.; from the head le and will be turned i1 this position when the scotometer partof the instrument is used. The meridan members 4;

`vill be designated on the rear surface ot llie ineml'ier G by the letters A, ll, C, eter. :is shown in Fig. 8, the letter il. beingr applied to the ineri ilian extending icrticall)v and ille other letters succ@ rely to the ribs Jl), as shoiifn iii Figs. il and 7.

oi' ineinbcr 2 likeii'ise f ri'adiialcd i. (ileific-.esy oil. '-i circle and cari-ics desig- .ns from Zero to 330, the Zero being loef" tlr icl t it "lV l f l l" tv .at ne im it. o Y t ie iiiii/ioiiia iiiiint, ti

e designations applied to the meridiaiis iii a co iiiteiclockirisc direction.

fr iiiodihed 'torni :lor holding the rnn 2 is shoiiii in and S. liistead olI this monili' i beiniiij rigidly7 secured in the briickct i, i bracketiis provided with the slot l@ fh eh open at its rea.' end ttor the ere; part, oi'i' its Width. il thumb screw ll joiirnaled in the bracket and a block 3er is fitted. at the rear ot thc. brac l." having; a shouldered portion eiiirztgiiin` be lower edge oit member 2 and project'- ver its rear surface. The block l2 l l ero, io

t to rccciie the. threaded ciid of n :no screw I an(r 'ie ineinner can l l l1 l tl l 0 ne claini'ied, between brackets Il and 'une block l2 by tiiihtcninp; this lliiiiiili Likewise. b v looseniiigi the tliiiinb sin ein the incinber 2 can be adjusted :infinu about its center in the bracket ll. iis construction. the incinlier Q car x a turning` nioi'cineiit ol" ien to twenty degrees to each .side ol its vertical axis. ,lliv liai'iiig` the handle portions l" disM i :is shown1 and the inenibei l projectN ng: torii'ardljf tliei'c'troni, the iiistriiniciil is niccliY balanced when hold in the hand aiiil 4has no dccideiV Lciidei'icji' to tilt` forwardlyv or reari'ardlji'. it also being' obvious that it is Well laanced laterally. The 'trent ol. thc nieinbor Q. trout surtace ot disk d and the 'liront sur'ace et the i'i'icridiaiis Alf, as ii'cll as the supporting` arias 1d, and tlif,` incnibci El. will all be painted black or coatcfl with :i blacl: naterial. llllilc in the ciiibodiniiiit oi' this invention illus rated.y the insii'unicnt is shown pifoi'iiled iritl :i handle :idaplcd lo be heldin the hand ol le pal ioni, it is with in the scope of thi iiiiheilioii to support the instrument upon a fixed bracket secured either te the wall or thor of ii roi'iiii. which bracket `will preteal'il'i7 lic located close to .ii ii'all or screen.

'I "he operation is as follows:

The instrument is preferably constructed. as shown, to be held in the hand of a. patient. rlie perimeter Will be broughtl So t iat the aperture 9a is substantiallj)i on a level with the eye and the member 1d pressed against the cheek below the eye, so that the lll() eye is substantially located at the center of the sphere. rlhe instrument is then held stationary by the patient who sights through the aperture 9a to the central aperture in the disk 8. While holding the instrument in this position with one hand, the sight objects 7 are moved outwardly on t-he meridians 4L until the same are just -at the edge of vision. These objects will usually be moved beyond the range of vision and will then be brought inwardly to a point where they can just be seen by the patient. By so positioning all of the light sight objects, it can be readily determined just what field of vision the patient has. This field of vision often varies in the three colors white, red and green, and if desired, the said field can be investigated for the other colors by using the red and green sight objects. When the scotometer portion of the instrument is to be used, the instrument is held in substantially the same position but the sight member 9 is then turned downwardly and the patient concentrates his gaze on the disk 8. Light can readily pass between the meridians l so that `a light back ground may be had. Also by holding the perimeter before colored screens or surfaces, any desire-d color of back ground may be used.

lt may sometimes be desired to determine the range of vision with more accuracy than can be done by the meridians 4lwhich are spaced circumferentially at angles of thirty degrees. With the construction shown in Figs. 2 and 8, the member 2 and meridians 4: can be turned circumferentially ten or twenty degrees and readings can thus be obtained on the meridians l with the samelocated at intervals of ten degrees. This more accurate determination may, of course be made at any portionof the field. The spots 8b shown on the scotometer disk are f r the purpose of investigating the socalled blind spots in the eye, which, as is well known, are caused by the connection or entrance of the optic nerve into the retina.

From the above description it will be seen that applicant has produced a perimeter which can be quickly manipulated by the patient or oculist accurately to determine the field of vision. There are no parts that need to be revolved to various positions, as in the perimeters of the prior art, yetV the instrument is light, convenient and eiiioient. The sight objects make a good contrast against the light passing between the meridians and the device is usable in most any degree of lighting. The open work form of the device also renders it light in weight so that it may be readily held in one hand and manipulated by the other. With such an instrument as herein disclosed, the patient can often quickly and accurately manipulate and adjust the instrument while the oculist is performing some other duty or attending another patient. As above inw dicated, the instrument may, if desired, be placed upon a fixed support and suitably disposed for the convenience of the patient.

lt will, of course, be understood that various changes may be made in the form, details and arrangement of the device without departing from the scope of applicants invention, which, generally stated, consists of the matter shown and described and set 4forth in the appended claims.

That is claimed is:

l. A. perimeter comprising a plurality of spaced relatively fixed meridian members arranged in diverging relation in a substantially semi-spherical surface, sight objects slidable on each of said members and disposed at the concave side thereof, the spaces between said members being open and unobstructed for substantially their entire extent whereby an open-work structure is provided in which light can pass between said members.

2. The structure set forth in claim l, a member joining the adjacent ends of said members and an annular member joining the other ends of said members.

3. A self-determining perimeter having in combination a plurality of equally spaced semicircular members disposed in and outlining substantially the surface of a semisphere the space between said members being free and unobstructed for substantially their entire extent, and disk objects movable thereon so as to be disposed and held at any position throughout the length thereof whereby a cage-like structure is formed in which light can pass between said members. 4. A perimeter comprising a plurality of equally spaced fixed semicircular meridian members radiating` from a common point and extending laterally to one side of said. point and symmetrically disposed about a horizontal extendingthrough said point, sight objects movable on said meridian members, and a sight member having a sight aperture located in the said horizontal axis at some distance from said point.

V5. rlhe st 1uctri'e set forth in claim 4L, and a disk disposed at the side of said members toward the sight having its center in the horizontal axis passing through the sight aperture and said point and having a small aperture at said center.

6. The structure set forth in claim 4e., a disk disposed onthe side of said meridian members toward the sight having its center in a horizontal axis passing through the sight aperture and said point and having a small central aperture therein, and a rim member joining the diverging ends of said meridian members.

7. The structure set forth in claim 4, a disk disposed on the side of said meridian members toward the sight member having its center in the horizontal axis passing through said point and the aperture ,in the sightmember and having a small central aperture therein, a rim member to which the diverging ends of the meridian members are connected, and a supporting means for said rim member.

8. A perimeter comprising a plurality of fixed equally spaced meridian members disposed in and outlining substantially th surface of a semisphere, a disk member lo cated on the inside of said members at the converging portions thereof having its central axis in the horizontal axis of said sphere and having a small central aperture therein, sight objects slidable on said meridian members and frietionally engaging the same to be held in theposition to which they are moved, and a gun sight having a sight aperture located in the horizontal axis of said sphere adjacent the center of the sphere.

9. The structure setforth in claim 8, and an annular rim member connecting the diverging 'ends of the meridian members.

10. The structure set forth in claim 8,

Van annular rim member conneetino' the diverging ends of the meridian members, and a supporting means for said rim member.

11. The structure set yforth in claim 8, an annular rim member connecting the diverging ends *of said meridian members, a supporting means for said rim member disposed at the lower central portion thereof, and a handle for said supporting means disposed a substantial distance to one side of the plane of said rim member toward the converging ends of the meridian members.

12. A perimeter comprising a plurality of relatively fixed rib members angularly spaced less than ninety degree apart, and sight objects slidably mounted thereon to be retainedY in any position to which they may be moved.

13. A perimeter vcomprising a series of angularly spaced rods disposed in a substantially semi-spherical surface, an annular member connecting the outer ends of said rods, a member connecting the inner ends of. said rods, the spaces between said members being substantially unobstructed, thus. forming a cage-like structure, a handle member in which said annular member is mounted and circumferentially movable.

14. An instrument comprising a perimeter having a plurality of fixed spaced and diverging meridian members With open and unobstructetd spaces therebetween, a disk located centrally thereof at the converging portions and having a small central aperturr` therein, said disk being marked to form a scotometer and sight objects frictionalhslidable on said meridian members and adapted to be moved from view in the rear of said disk.

15. An instrument comprising a perimeter comprising spaced rods disposed in the surface of the semisphere, an apertured disk member carried thereby at the center of said surface, a sight member having an aperturev located substantially at the center of the sphere defined by said surface cri-operating with said disk aperture, said disk constitut' ing a scotometer, and said sight inelnber hcing constructed and arranged to be moved to inoperative position when the scotometer is used.

16. A perimeter comprising a plurality of fixed meridian members radiatingr from a common point and projecting to one side thereof and angularly spaced less than 180 degrees apart, a member to which the inner ends of said members are connected, and an annular member to which the outer ends of said. members are connected.

17. A perimeter comprising a plurality of fixed spaced meridian members radiating from a common point in planes intersectingr at angles less than 180 degrees and making equal angles With a vertical plane passing through said point, and means joining the outer ends of said members.

18. A perimeter comprising a plurality o f relatively fixed substantially se1ni-eircular meridian members spaced less than ninety degrees apart. supporting means at both ends thereof` the spaces between said nicmbers and said supporting means being open and unobstructed for substantially their entire extent and said meridian members being visible from the concave side of the perimeter.

19. A perimeter comprising a plurality of rod-like members radiating from a common point and making equal angles with a ver tical plane passing through said point` said members being angularly spaced less than 180 degrees apart, and an annular means connecting the outer ends thereof said memm bers being visible from a point in the pl ano of and enclosed by said annular means.

In testimony whereof I afiix my signature.

HOVVAR-D Mol.. MORTON. 

